The former Made In Chelsea star looked fresh as a daisy as she posed in her cute-as-pie getup, as UK temperatures soared once again.
And while we've previously spotted her in many a designer frock, Millie proved she's a high street girl at heart in her adorable one-piece, which comes from Miss Selfridge.
She kept the rest of her look simple, adding a black crop tee from Graffic whilst accessorising her bronzed pins with espadrille wedges by Pied A Terre.
But it's not just her wardrobe we're lusting after - the fashionista showcased her naturally flawless complexion with a barely-there make-up look, adding her Millie Mackintosh Lashes in City, £8.99, for extra oomph.
Effortless chic at its best - good work, Mills!
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